Ducted spinner inlet



Nov. 20, 1951 T. E. GRIMAC f 2,575,415

DUCTED SPINNER INLET Filed Oct. 15, 1948 Patented Nov. 1951 I* 'Y l- 2,575,415

UNIT-ED g. Nar/5,415 l l lL'DUCIDsPINNER 'INLET m to United Aircraft Corporation, East Hartford,l l

Conn.; a"'corpor'ation of Delaware? 'Y l 'y l.. Y

. 1 Awliffon Garter 15, leia'slrialriq- 54,735.

' 4 Claims.- (Cl. Hogwarts) f'g'A This invention relates'to 'a'ductedinlet foruse pressed air is vdischarged 'through' one orsmore particularly with aircraft power plants vand burners I to a turbine 8, the function of which is 'adapted to remove any water Aoric'e particles or todrifve the compressor and valso the propeller other foreign matter from the air passing through `system 1I I). From the turbine'. the exhaust gas Iis the inlet. t t Y discharged' through a thrust nozzle I2. s "Foreign matter, such as dustor other small The compressor 2 has an annular inlet and it particles in the air, are detrimental to the operis essential for best operation of the power plant fation of power plants,` particularly' gas turbine that `Vthe flowto all sections ofthe compressor Ato the operative parts of the power plant. Furtypes, since the particles may scratch 'or mar the inlet vbe the same for any selected operating consurface' over which the air flows ortmayv collect i0 dition; y One arrangement for accomplishing this on` the surface and in the Aair passage thereby is Aby the ducted spinnerinlet shown inrgreater Virnpeding eicient flow of ar'to the'p'ower plant. detail in Fig. 2. t. u Larger particles maysimila'rly accumulate on the As shown, the yair inlet includes an outer` memsurface ofthe air passage and also cause damage ber `I4 or duct having an inlet passage I6, the wall of which is cylindrical, in the arrangement shown. thermore, the large amount of` airl required for a Thereafter, adiverging wall surface I8 on memgas turbine power plant necessitates an arrangeber` I4 forms a diverging passage Vdirectly comment to remove foreign material from a very municating with the circular inlet passage. I6. large mass of air, with the structureby which The member I 4,V is mounted on' the cuifs 20 that impurities are removed offering as littleresistance U ysurround the Shanks 22 of thefpropeller blades 24 as possible to the flow of air, thereby maintaining of the propeller system. The blades are supported an eicient operation of the power plant.V Affeaby a central element or hub 26, the upstream end -ture of the invention is an arrangement for reofwhich is located adjacent tofthe upstream end 'moving the particlesof foreign matter vfrom an of the diverging wall portion I8. The outer wall air *inletA with -a small pressure drop throughthe ofthe hub 28 is approximately parallel to the device. Another feature is an arrangement for inner wall 3U of the outermember I4, thereby disposing of the foreign material-as it is collected 4defining an annular air path '32, the rearward by the separating structure. part"33 of which communicates directly with the VIn addition to removing solid particles, it is compressor inlet. The propeller cuffs 2B extend advantageousbto remove water which may be in 30 outwardly from the central element 26 and may the form of rain or ice from the air entering the beconstructed to form struts or guide vanes for compressor of the powerplant'. A feature of the the air owing through the passage 32.

invention'is an arrangement for removing .water t `-'I'he upstream end of theinner element 26 has or Yice from the' air 'as it enters'the powerY plant 'a're'c''ss' 34"wh`iclireceives foreign particles from without aifecting the ow of air so that it may the airentering the power plant. The recess is reach the annular inlet of the compressor with no 1 slightly larger in diameter than the inlet passage serious pressure losses. Under severe conditions I6 and is in alignment therewith so that all of the the mechanism that Collects the impurities may air entering the annular passage 32 is caused to tlll in a short time. Another feature of the inchange its direction as shown by the arrows 36` VentiOn iS an arrangement fOr disposing of the 40 with the result that any impurities therein are collected foreign material by causing it to flow thrown out by centrifugal force and are received through passages, the discharge ends of which are in the recess 34. Foreign particles are collected externally 0f the air inlet within the recess 34 and discharged through pas- Other objects and advantages may be apparent sage 38 located in the inner member 26, the cuffs from the specification and claims and from the 2U, and the spinner I4. The curvature of these aCCOmpanyng drawing Which illustrates an elnpassages is such that the centrifugal'action on the bodiment of the invention. I particles of foreign matter assists in the lnow of Fig. 1 is an elevation of the power plant insuch particles through the passages for their re'- corporating the ducted inlet. moval. It will also be apparent that the inlet y Fig. 2 is a fragmentary, longitudinal View on 50 end of these passages is located adjacent to the a larger scale of the inlet. outer diameter of the recess 34 since it is in these The invention is shown in connection with an corners of the recess that the impurities will be aircraft power plant of the gas turbine type in collected by the centrifugal force as the device which an axial flow compressor 2 receives air rotates.

,through the ducted spinner linlet 4. The com- In addition to providing the hub with the up,

standing wall 4U which surrounds the recess and projects upstream from the hub, the recess may have a central cone 42 located centrally of the hub and having the apex of the cone pointed upstream. The purpose of the cone is to cause the air entering the power plant to be directed outwardly, thereby moving the air in a direction to improve the ow of', air into thegannular inlet.

Withjthisarrangement, there in eieti'ia circular path for the inlet air which extends to the base of the recess 34, with the annular path e 32 communicating therewith forwardly Y giftige downstream end of the circular path. i Y Since many of the impurities that are removed from the air are water or li ce,' i`t maybe ad'van-k tageous to provide for heating thecential'ele-H.

ment adjacent to the recess "34, as byna coiln 1 4 to prevent the rapid accumulation of icetherein.V

Further, if desired, it may be advantageous kto provide for heating of the passage`38 through whichv thehimpurities .are discharged. fromA th J ma obeuuderstoedt t. .traag-to the' specic embed; trated and` described, but may W ys without: departure from ingl b :path-for ar Y, aid'jcutermemberfups has/ing a cylindrical g air'in ingwith saidannularjpath'. l 'sybstantially'smaller thanth'ef.` propeller' hllthe 'latt'e'r vhaving .al recess in'its up'strean en in alignmentj7 with 'and sulzlsirantially'k the" gthecylindricalfair inletwherebyjPtlie l saidfcylindrical. inlety is turnedltqgcentr' ug'ally uispqseof impurities thereiuprio; tou ingj *te isaidjannular path,andpropellerlbia mils on 'said Ahub and .extending "outwardlyforesupport? ing said outer jmembelgithe Zanrnil'fary,.'pjajssage a'rg'mncl saidwhupvjcommunicatixig Iwi'tlilftli 'aar compressor'inlet.1,' An 'air inlet forja powerpl'antfjsaid pow plantincludine 'a compressorhavine fniietffsaidiniet including-ia propeller' mi bg "lngbetweenjsaidj hub'iandA member. ka A, path for air, said outer mernher upstream pltlie `hub havinga cylindrical air inletpoinmunicating with said annular path and having an area suizo1 stantially smaller than the propeller hub, the latter having a recess in its upstream end in alignment with and substantially the area of the cylindrical air inlet, and propeller blade cuffs on said hub and extending outwardly for supporting said outer member, the annular passage around said hub communicating withthe. annular comat least one of said cuffs and communicating with 7said recess for the discharge of foreign matter 'collecting therein.

'l 3. 'ducted spinner for an aircraft propeller comprising ampropeller hub located centrally of lthefspinner'md spaced therefrom in predeterfmjned;relationtherewith, said spinner and hub forming anannular passage, an air inlet in said sp'iiirer 'spa'd upstream oi said hub and com- ,mllyiating with said annular passage, means carried by said hub for turning the flow of air igrkrning?i protrusions .v .directedin ,Y an .difutfofln aumen-shelf in.

' vmeans communicating. with`f'sa1d recess 'andiextrauuag said-spi@ v reg. ai en the-'oreig'n matten acuilul ing ,in

Y aSSa-ge 

